Edge-lighted panel arrangement

ABSTRACT

An edge-lighted panel having a number of light sources coupled to a length of flexible wiring which is arranged to be removably affixed about the peripheral edge of the panel, with the light sources disposed within light receiving cavities in the marginal portion of the panel.

United tau W1, 12 u Pulles EDGE-LIGHTED PANEL ARRANGEMENT Eduard ,l.Pulles, Huntsville, Ala.

GTE Automatic Electric Laboratories Incorporated, Northlake, 111.

Filed: Nov. 2, 1973 Appl. No.: 412,237

Inventor:

Assignee:

US. Cl 240/1 EL; 240/2.1; 350/96 R Int. Cl. F21 Field of Search 240/1EL, 2.1, 6.43, 2.17;

References Cited UNITED STATES PATENTS Hoff 240/1 EL July 1, 19752,988,631 6/1961 Hershey et a1 240/1 EL 3,497,686 2/1970 Young 350/96 R3,752,974 8/1973 Baker 240/1 EL 3,760,175 9/1973 Gibson et all 240/1 ELPrimary ExaminerRichard L. Moses Attorney, Agent, or FirmRobert 1. Black[5 7 ABSTRACT An edge-lighted panel having a number of light sourcescoupled to a length of flexible wiring which is arranged to be removablyaffixed about the peripheral edge of the panel, with the light sourcesdisposed within light receiving cavities in the marginal portion of thepanel.

7 Claims, 3 Drawing Figures 1 EDGE-LIGHTED PANEL ARRANGEMENT Thisinvention relates to an improvement in edgelighted-panels.

Edge-lighting has been used for illuminating instrument dials, panels,plotting boards for shipboard and aircraft'aswell as other similarpurposes. The illumination of 'such devices generally is by means of oneor more light sources located at the edge of a transparent panel andlight rays introduced into the panel for transillumination thereof andindirect illumination thereby. Various arrangements for edge-lightingvarious types of panels are disclosed in US. Pat. Nos. 3,027,669;3,070,913; and 3,356,839. The edge-lighting in these prior disclosuresare attached to the panels by means of frame'members adapted to supporttherein a number of lamps or by means of light sockets affixed in somesuitable fashion to the panel.

In accordance with the present'invention, a convenient, low-cost methodof lighting a panel using contemporary components and techniques isprovided. A piece of flexible wiring or circuit snaps onto the panel tobe lit, and the terminals form an integral part of the flexible wiringstrip. Light emitting diodes are mounted on the flexible wiring and fitwithin recesses formed in the panel.

Accordingly, it is an object of the present invention to provide aconvenient, low-cost method of edgelighting a panel.

The invention, together with the above and other objects and advantagesthereof, is set forth in more detail in the following description whenconsidered in connection with the accompanying drawings wherein likereference numerals designate like parts throughout the several viewsthereof, and wherein:

FIG. 1 is a perspective view of an edge-lighted panel exemplary of theinvention;

FIG. 2 is a top plan view of the edge-lighted panel of FIG. I; and

FIG. 3 is an enlarged view generally illustrating the snap-on feature ofthe flexible wiring.

Referring now to the drawing, a panel or light transmitting member madeof glass or a highly transparent plastic is edge-lighted by a length offlexible wiring or circuit 12 having light emitting diodes 14 mountedthereon which is removably secured about the peripheral edge of thepanel. In the illustrated embodiment, the panel 10 may form a part of alighted touch calling telephone, and functions to illuminate a pushbutton, such as the push button 16.

The panel or light transmitting member 10 comprises a relatively flat,highly transparent plate, having its front and back surfaces in parallelrelation to each other and preferably polished to provide smooth opticalsurfaces. It is preferably fabricated from an acrylic resin or methylmethacrylate plastic material of the thermal plastic type such as, forexample, commercial Plexiglas or Lucite. The bottom surface of the panelor light transmitting member 10 preferably is made reflective, by somesuitable means, such as a coating with mirror silver. The coating shouldbe opaque so that no light escapes from the bottom surface of the panel,and all is reflected upwardly. The upper surface should be formed to betranslucent and diffusing, and non-transparent, so as to minimize spotsof excessive brilliance and achieve a softly diffused pool of light overthe upper surface. A number of recessed cavities 18 which may besemi-circular in shape as illustrated are formed in spaced relationshipabout the peripheral edge of the panel 10 and, with the exception ofthese cavities, the edges of the panel 10 are sandblasted or painted tomake them opaque so that no light escapes.

A length of flat flexible wiring or circuit which may be, for example, alength of flat flexible plastic material having an electrical conductoror conductors imbedded therein has a number of light emitting diodes l4affixed to it and electrically coupled with the conductor or conductorsso as to be energized when the flexible wiring or circuit is connectedto an appropriate power source (not shown). The light emitting diodes 14are positioned on the flexible wiring or circuit 12 to fit within thecavities 18 in the edge of the panel 10, when the flexible wiring orcircuit 12 is affixed to the panel, as described more fully below.

The flexible wiring or circuit 12 preferably is removably affixed to thepanel 10, and this can be accomplished in various different manners,using snapfasteners or the like. A preferred manner of doing so, becauseof its simplicity and inexpensiveness is to form a number of projections20 on the peripheral edge of the panel 10, and to provide the flexiblewiring or circuit with a number of openings 22 which are formed andpositioned to receive therethrough these projections 20. The shape ofthe projections 20 and the openings 22 in the flexible wiring or circuitmay vary, but preferably both are shaped and proportioned to provide asnap-on feature.

For the purpose of establishing a connection with the power source (notshown) the flexible wiring or circuit can have a terminal 25 on each ofits opposite'ends, as illustrated, or two terminals can be provided onone end thereof.

From the above description of the edge lighted panel arrangement, it canbe seen that the flexible wiring or circuit 12 can be easily and quicklyaffixed to the panel 10, simply by snap-fitting the projections 20 onthe edge of the panel through the openings 22 in the flexible wiring orcircuit. By properly positioning these projections and the openings, aswell as the light emitting diodes 14 thereon, the light emitting diodeswill be disposed within the cavities 18 formed in the edge of the panel10. Thereafter, the terminals 25 on the end or ends of the flexiblewiring or circuit is connected to the power source to energize the lightemitting diodes. The lighting can be easily and quickly removed andreplaced, simply by removing the flexible wiring or circuit andsnap-fitting a new length of it onto the panel 10 in the mannerdescribed.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained andcertain changes may be made in carrying out the above method and in theconstructions set forth. Accordingly, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

Now that the invention has been described, what is claimed as new anddesired to be secured by letters Patent is:

1. In combination, a transparent light-transmitting panel having frontand rear surfaces arranged for specular reflection of light therebetweenand a marginal portion for receiving light, said marginal portion beingprovided with a plurality of spaced openings for receiving light sourcesand with a plurality of spaced fastening means, a length of flexiblematerial carrying electrical conductor means and having a plurality ofcomplimentary fastener means for fastening with the fastening means onsaid marginal portion of said panel. a plurality of light sourcescarried by said length of flexible material and electrically connectedwith said electrical conductor means so as to be energized when saidelectrical conductor means is connected to a source of power, saidlength of flexible material being affixed about said marginal portion ofsaid panel by mating together said fastening means, said plurality oflight sources being positioned on said length of flexible material so asto be disposed within said spaced openings when said flexible materialis affixed to said panel, whereby edge-lighting for said panel can beprovided simply by affixing said flexible material to said panel andcoupling the electrical conductor means to a source of power.

2. The combination of claim 1, wherein said fastening means on saidpanel comprises a plurality of projections and wherein said fasteningmeans on said flexible material comprises a plurality of openings insaid flexible material proportioned to receive said projections topermit said flexible material to be affixed to said panel.

3. The combination of claim 1, wherein said flexible material hasconnector means on one end thereof for coupling said electricalconductor means to a source of power.

4. The combination of claim 1, wherein said flexible material hasconnector means on each of the opposite ends thereof for coupling saidelectrical conductor means to a source of power.

5. The combination of claim 1, wherein said plurality of light sourcescomprise light emitting diodes.

6. The combination of claim 1, wherein said length of flexible materialis a plastic material having said electrical conductor means imbeddedtherein.

7. The combination of claim 1, wherein said length of flexible materialis a plastic material having a metallic conductor deposited thereon toprovide said electrical conductor means.

1. In combination, a transparent light-transmitting panel having frontand rear surfaces arranged for specular reflection of light therebetweenand a marginal portion for receiving light, said marginal portion beingprovided with a plurality of spaced openings for receiving light sourcesand with a plurality of spaced fastening means, a length of flexiblematerial carrying electrical conductor means and having a plurality ofcomplimentary fastener means for fastening with the fastening means onsaid marginal portion of said panel, a plurality of light sourcescarried by said length of flexible material and electrically connectEdwith said electrical conductor means so as to be energized when saidelectrical conductor means is connected to a source of power, saidlength of flexible material being affixed about said marginal portion ofsaid panel by mating together said fastening means, said plurality oflight sources being positioned on said length of flexible material so asto be disposed within said spaced openings when said flexible materialis affixed to said panel, whereby edge-lighting for said panel can beprovided simply by affixing said flexible material to said panel andcoupling the electrical conductor means to a source of power.
 2. Thecombination of claim 1, wherein said fastening means on said panelcomprises a plurality of projections and wherein said fastening means onsaid flexible material comprises a plurality of openings in saidflexible material proportioned to receive said projections to permitsaid flexible material to be affixed to said panel.
 3. The combinationof claim 1, wherein said flexible material has connector means on oneend thereof for coupling said electrical conductor means to a source ofpower.
 4. The combination of claim 1, wherein said flexible material hasconnector means on each of the opposite ends thereof for coupling saidelectrical conductor means to a source of power.
 5. The combination ofclaim 1, wherein said plurality of light sources comprise light emittingdiodes.
 6. The combination of claim 1, wherein said length of flexiblematerial is a plastic material having said electrical conductor meansimbedded therein.
 7. The combination of claim 1, wherein said length offlexible material is a plastic material having a metallic conductordeposited thereon to provide said electrical conductor means.